The present invention relates to bar locking systems and, in particular, to a bar lock apparatus having a key-actuated high-security core. More particularly, the present invention relates to a bar lock apparatus having a bolt mechanism that is releasable for service or replacement by removing the high-security core from its mounted position within the bar lock apparatus.
Conventional bar lock assemblies include a pair of interengageable plates and a bar lock mechanism slidably received in a bore defined by the plates. It is known to use a hidden set screw to couple the bar lock mechanism to one of the plates, thereby limiting the range of axial movement of the slidable bar lock mechanism in the plate bore. See, for example, U.S. Pat. Nos. 3,827,266; 3,899,905; 3,921,422; and 3,940,957 to Walters.
It is necessary to operate the above-noted hidden set screw to permit removal of the bar lock mechanism from the plate bore for service or replacement. Since each known plate is typically bolted and welded to its underlying door panel or the like, it becomes a troublesome and often time-consuming problem to remove the welded plates from their mounted positions to gain access to the head of the hidden set screw. Such a problem typically exists for known bar lock assemblies each time it becomes necessary to service or replace the bar lock mechanism.
One object of the present invention is to provide a bar lock system configured to permit a service representative to remove the bar lock mechanism for service easily in the event that it malfunctions or requires cleaning without having to take the entire unit off the door.
Another object of the present invention is to provide a bar lock system wherein the slidable bar lock mechanism is key-actuated to permit removal of the bar lock mechanism for service solely by operation of a control key inserted into a core provided in the bar lock mechanism.
Yet another object of the present invention is to provide a key-actuated bar lock system which is conveniently modifable in the field to prevent removal of the operating key from the bar lock mechanism when the key is in the lock and the bar lock mechanism has been moved to an unlocked position.
In accordance with the present invention, a bar lock system is provided for lockably connecting two adjacent panels together. The bar lock system includes a pair of matable plates. One plate includes an inner wall defining an axial bore having opposite forward and rearward openings. A bar lock mechanism is positioned within the axial bore for sliding movement therein.
Retaining means is also provided in the bar lock system for releasably retaining at least a portion of the bar lock mechanism in the axial bore of the one plate. The retaining means operates to prevent unauthorized removal of the bar lock mechanism from the axial bore through the rearward opening. The retaining means moves within the axial bore in directions substantially parallel to the longitudinal axis of the axial bore between a retaining position obstructing removal of the bar lock mechanism from the axial bore and release positions.
In preferred embodiments of the present invention, the one plate includes stop means in its axial bore for blocking forward movement of the bar lock mechanism therein past a predetermined location following introduction of the bar lock mechanism into the axial bore through the rearward opening. Thus, the stop means operates to prevent unauthorized removal of the bar lock mechanism from the axial bore through the forward opening.
The one plate includes a rearward portion extending between the stop means and the rearward opening. The rearward portion is formed to include an F-shaped pin-receiving slot having an opening in the inner wall. In addition, the bar lock mechanism includes pin means for lockably engaging the pin-receiving slot to retain the bar lock mechanism in at least one selected position within the axial bore in said one plate.
The bar lock mechanism is formed to include a forwardly opening core-receiving chamber. The retaining means includes a lock core, a lock cap having an inner face, and means for mounting on the lock core. The lock core includes control-lug means for selectively retaining a portion of the lock core in the core-receiving chamber to position the inner face of the mounted lock cap in spaced-apart confronting relation to the stop means. In use, the inner face of the lock cap engages the stop means during rearward movement of the bar lock mechanism in the axial bore to prevent unauthorized removal of the bar lock mechanism from the axial bore through the rearward opening.
The stop means is rigidly fixed to the inner wall and extends into the axial bore a predetermined distance to provide a forwardly presented blocking surface for engaging the inner face of the lock cap. Thus, the stop means acts to define the predetermined location at which rearward movement of the bar lock mechanism in the axial bore is blocked.
The lock cylinder means includes an exterior side wall formed to include an aperture therein and the lock core includes a key-actuated rotatable key plug. The pin means includes throw member means for engaging the key plug, support means for rotatably mounting the throw member means in the lock cylinder means to rotate with the key plug, and a locking pin having a proximal end fixed to the throw member means and a distal end extending through the side wall aperture for engagement with the pin-receiving slot.
In one embodiment, the pin-receiving slot and the pin means are configured to prevent removal of an operating key from its operating position within the bar lock mechanism. In this embodiment, the F-shaped pin-receiving slot has a selected side branch formed to include a specially configured flanged side wall. That side wall is flanged to block entry of a wide cylindrical locking pin, thereby providing a barrier to rotation of the key plug and throw member means and preventing removal of the operating key from the key plug when the bar lock mechanism is in its unlocked position. In another embodiment, the locking pin has a stepped distal end configured to mate with the flanged side wall and enter the selected side branch upon rotation of the key plug, thereby allowing a user to remove the key from the key plug in either the locked or unlocked position of the bar lock mechanism.
One feature of the present invention is the provision of bar lock mechanism retaining means which is movable within the axial bore in directions substantially parallel to the longitudinal axis thereof. This feature advantageously enables a service representative to release the normally captive bar lock mechanism simply by moving the retaining means in an axial direction within the axial bore that does not require detachment of either one of the plates from its door panel. Avoidance of such a detachment step during each service call advantageously lessens risk of damage to the plates and to the bar lock mechanism itself, reduces service time, simplifies service operations, minimizes inventories of replacement plates and related hardware typically needed to replace damaged components, and lessens overall costs of service.
Another feature of the present invention is the inclusion of a lock core in the retaining means having a lock cap and control-lug means for retainably positioning the lock cap in spaced-apart confronting relation to the stop means. Advantageously, the lock cap engages the stop means during withdrawal of the bar lock mechanism through the rearward opening, thereby blocking unauthorized removal. In addition, such locking cap "blocking means" is easily disabled by using a control key to operate the control-lug means and remove the lock core from its mounted position within the bar lock mechanism. Such a feature is a significant improvement over conventional retaining means of the type described above which generally require operation of a difficult-to-access hidden set screw to effect the release of a bar lock mechanism for service or replacement.
Yet another feature of the present invention is the configuration of the F-shaped pin-receiving slot to include a flanged side branch for controlling the operation of the locking pin. In one embodiment, the locking pin has a stepped distal end configured to slide into and engage the flanged side branch to permit removal of the operating key from the key plug when the bar lock mechanism is in its unlocked position. Alternatively, in another embodiment, the locking pin has a wide distal end that is too large to be inserted into the flanged side branch, thereby preventing removal of the operating key from the key plug when the bar lock mechanism is in its unlocked position. Advantageously, merely by replacement of the locking pin, the bar locking system of the present invention is adaptable either to permit or prevent removal of the lock-operating key when the bar lock mechanism is in its unlocked position. This feature enhances the key control and operational versatility of the improved system.
Additional objects, features, and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of a preferred embodiment exemplifying the best mode of carrying out the invention as presently perceived.